Bronchodilator effect on ventilatory, pulmonary gas exchange, and heart rate kinetics during high-intensity exercise in COPD

The purpose of this study was to examine oxygen consumption (V˙o 2) and heart rate kinetics during moderate and repeated bouts of heavy square-wave cycling from an exercising baseline. Eight healthy, male volunteers performed square-wave bouts of leg ergometry above and below the gas exchange threshold separated by recovery cycling at 35%V˙o 2 peak.V˙o 2 and heart rate kinetics were modeled, after removal of phase I data by use of a biphasic on-kinetics and monoexponential off-kinetics model. Fingertip capillary blood was sampled 45 s before each transition for base excess, HCO[Formula: see text] and lactate concentration, and pH. Base excess and HCO[Formula: see text] concentration were significantly lower, whereas lactate concentration and pH were not different before the second bout. The results confirm earlier reports of a smaller mean response time in the second heavy bout. This was the result of a significantly greater fast-component amplitude and smaller slow-component amplitude with invariant fast-component time constant. A role for local oxygen delivery limitation in heavy exercise transitions with unloaded but not moderate baselines is presented.

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Impact of a combined diet and progressive exercise intervention for overweight and obese children: the B.E. H.I.P. study

Applied Physiology Nutrition and Metabolism ◽

10.1139/h11-042 ◽

2011 ◽

Vol 36 (4) ◽

pp. 515-525 ◽

Cited By ~ 8

Author(s):

Patricia K. Doyle-Baker ◽

Allison A. Venner ◽

Martha E. Lyon ◽

Tak Fung

Keyword(s):

Heart Rate ◽

Waist Circumference ◽

Fat Mass ◽

High Intensity ◽

High Intensity Exercise ◽

Obese Children ◽

Intervention Programme ◽

Progressive Exercise ◽

Exercise Class ◽

Health Intervention Programme

The Biochemical Evaluation of a Health Intervention Programme (B.E. H.I.P.) investigated the impact of progressive exercise intensity in overweight and obese children. A 5-month prospective randomized crossover design (XA, immediate intervention; OB, control group; XB, delayed intervention, OA, postintervention follow-up) with a 10-week health intervention programme was employed. The intervention utilized a progressive increase in high-intensity exercise (≥75% maximum heart rate) and included 3 nutrition and 2 parent education sessions. Primary analysis was completed with (i) XA versus OB and (ii) all intervention participants (collapsed XA and XB = XAXB). Prepubertal overweight and obese male and female children (n = 27) between 5 and 10 years of age were randomly allocated to XA (n = 16; 11 females; waist circumference = 80.0 ± 10.6 cm) or OB (n = 11; 3 females; waist circumference = 76.6 ± 7.5 cm). The primary variables were heart rate and percent fat mass. All variables, including body composition, habitual activity, and serum lipids, were repeatedly measured for up to a maximum of 7 time points. Energy expenditure was quantitatively measured throughout each exercise class (n = 20). A significantly longer time in the exercise sessions was spent in high-intensity (35.1%–60.0%) versus low- to moderate-intensity (64.9%–40.0%) exercise as the intervention progressed from the first to the last attended exercise class (Fisher exact test, p < 0.0001). The percent fat mass decreased in all intervention participants (–2.2%, p < 0.0001). XA had a greater slope decrease than OB for percent fat mass (p = 0.00051) and triglycerides (p = 0.0467). In conclusion, high-intensity exercise, within a comprehensive health programme that includes nutrition education, improved the lipid and physiological health profiles of obese children.

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The Effects of Physical Fitness and Body Composition on Oxygen Consumption and Heart Rate Recovery After High-Intensity Exercise

International Journal of Sports Medicine ◽

10.1055/s-0031-1295442 ◽

2012 ◽

Vol 33 (08) ◽

pp. 621-626 ◽

Cited By ~ 7

Author(s):

E. Campos ◽

F. Bastos ◽

M. Papoti ◽

I. Freitas Junior ◽

C. Gobatto ◽

...

Keyword(s):

Heart Rate ◽

Body Composition ◽

Oxygen Consumption ◽

Physical Fitness ◽

High Intensity ◽

Heart Rate Recovery ◽

High Intensity Exercise

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Exercise training intensity determination in cardiovascular rehabilitation: Should the guidelines be reconsidered?

European Journal of Preventive Cardiology ◽

10.1177/2047487319859450 ◽

2019 ◽

Vol 26 (18) ◽

pp. 1921-1928 ◽

Cited By ~ 8

Author(s):

Dominique Hansen ◽

Kim Bonné ◽

Toon Alders ◽

Ann Hermans ◽

Katrien Copermans ◽

...

Keyword(s):

Cardiovascular Disease ◽

Heart Rate ◽

Exercise Intensity ◽

High Intensity ◽

Ventilatory Threshold ◽

Cardiopulmonary Exercise Test ◽

High Intensity Exercise ◽

Cardiovascular Rehabilitation ◽

Correct Determination ◽

Low Intensity Exercise

Aims In the rehabilitation of cardiovascular disease patients a correct determination of the endurance-type exercise intensity is important to generate health benefits and preserve medical safety. It remains to be assessed whether the guideline-based exercise intensity domains are internally consistent and agree with physiological responses to exercise in cardiovascular disease patients. Methods A total of 272 cardiovascular disease patients without pacemaker executed a maximal cardiopulmonary exercise test on bike (peak respiratory gas exchange ratio >1.09), to assess peak heart rate (HRpeak), oxygen uptake (VO2peak) and cycling power output (Wpeak). The first and second ventilatory threshold (VT1 and VT2, respectively) was determined and extrapolated to %VO2peak, %HRpeak, %heart rate reserve (%HRR) and %Wpeak for comparison with guideline-based exercise intensity domains. Results VT1 was noted at 62 ± 10% VO2peak, 75 ± 10% HRpeak, 42 ± 14% HRR and 47 ± 11% Wpeak, corresponding to the high intensity exercise domain (for %VO2peak and %HRpeak) or low intensity exercise domain (for %Wpeak and %HRR). VT2 was noted at 84 ± 9% VO2peak, 88 ± 8% HRpeak, 74 ± 15% HRR and 76 ± 11% Wpeak, corresponding to the high intensity exercise domain (for %HRR and %Wpeak) or very hard exercise domain (for %HRpeak and %VO2peak). At best (when using %Wpeak) in only 63% and 72% of all patients VT1 and VT2, respectively, corresponded to the same guideline-based exercise intensity domain, but this dropped to about 48% and 52% at worst (when using %HRR and %HRpeak, respectively). In particular, the patient’s VO2peak related to differently elicited guideline-based exercise intensity domains ( P < 0.05). Conclusion The guideline-based exercise intensity domains for cardiovascular disease patients seem inconsistent, thus reiterating the need for adjustment.

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